As you are well aware, we have foot-and-mouth disease in the UK and export of animals and meat have been banned. As a result, the price of lambs has fallen during the peak of our marketing season - to the severe detriment of lamb producers.

However, our largest supermarket, Tesco, is selling New Zealand lamb, which comes at a cost to the environment of 12,000 food miles and has been killed for at least eight weeks, which makes it old season lamb.

There has always been a season for NZ and UK lamb, but NZ ­appears to be breaching this ­arrangement. This is unnecessary as, due to the ban on UK exports, the market is wide open on the Continent for NZ lamb.

I wrote to Sir Terry Leahy and he replied: "We import very little produce and only do so where the product can not be bought in the UK or to ensure that we can meet demand from customers.

"I hope that this has assured you of our continued commitment to British agriculture and, of course, our customers."

The reason they are marketing NZ lamb is for higher profit margins at the expense of their customers, because they can buy this old season lamb for less than new season British and are charging their customers the same price.

The selling price per kilo is identical, but the NZ meat is poor quality, old, discoloured and fat.

There is an abundance of UK lamb available, but St Merryn Meats, which kills and processes 85% of all red meats that go to Tesco, is not slaughtering lambs to capacity because it does not have the orders from Tesco. This shows that Leahy has no commitment to either British farmers, his customers or Tesco's carbon footprint. He has a greater commitment to higher profit margins.

Within three miles of the store in Pulborough, 1,600 lambs are reared annually.